Question
In a group of 200 students, 120 read newspaper
A, 90 read newspaper B, 80 read newspaper C, 50 read both A and B, 40 read both B and C, 30 read both A and C, 20 read all three newspapers. How many students read exactly one newspaper?Solution
ATQ, Let A, B, C be the sets. Exactly two-set counts: A∩B only = 50 − 20 = 30 B∩C only = 40 − 20 = 20 A∩C only = 30 − 20 = 10 Only A = 120 − (30 + 10 + 20) = 120 − 60 = 60 Only B = 90 − (30 + 20 + 20) = 90 − 70 = 20 Only C = 80 − (10 + 20 + 20) = 80 − 50 = 30 Students with exactly one newspaper = 60 + 20 + 30 = 110.
The average of four consecutive odd numbers is 47. What is the largest of these numbers?
X and Y have weights of 36 kg and 60 kg, respectively. Z weighs 12 kg less than X. Calculate the average weight of X, Y, and Z.
The average number of books sold by Viren in first 5 months is 3000 and in first 6 months is 3800. If the number of books sold by him in 7th ...
The average marks scored by 32 boys and 38 girls are 70 and 92 respectively. Find the average marks scored by all the students together. (Answer should ...
A number is such that when it is multiplied by 4, it gives another number which is as much above from 180 as the original number (itself) is below 180. ...
- The incomes of ‘X’, ‘Y’, and ‘Z’ are in the ratio 5:6:9, respectively. The average income of the three is Rs. 15,000. If ‘X’, ‘Y’, and ...
The average of two consecutive even numbers is 69. If the smaller number is increased by 10% and the larger number is decreased by 10%, then find the di...
The average height of 8 boys in a basketball team is 180 cm. If the tallest boy leaves, the average becomes 175 cm. Find the height of the boy who left.
The average weight of 14 persons increases by 3.5 kg when a new person comes in place of one of them weighing 48 kg. The weight of the new person is.
Find the average of prime numbers between 20 and 40.
